text: // This is an open source non-commercial project. Dear PVS-Studio, please check
  // it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
  
  #define EXTERN
  #include <assert.h>
  #include <msgpack.h>
  #include <stdbool.h>
  #include <stdint.h>
  #include <string.h>
  
  #include "nvim/ascii.h"
  #include "nvim/autocmd.h"
  #include "nvim/buffer.h"
  #include "nvim/channel.h"
  #include "nvim/charset.h"
  #include "nvim/decoration.h"
  #include "nvim/decoration_provider.h"
  #include "nvim/diff.h"
  #include "nvim/eval.h"
  #include "nvim/ex_cmds.h"
  #include "nvim/ex_cmds2.h"
  #include "nvim/ex_docmd.h"
  #include "nvim/ex_getln.h"
  #include "nvim/fileio.h"
  #include "nvim/fold.h"
  #include "nvim/getchar.h"
  #include "nvim/hashtab.h"
  #include "nvim/highlight.h"
  #include "nvim/highlight_group.h"
  #include "nvim/iconv.h"
  #include "nvim/if_cscope.h"
  #include "nvim/lua/executor.h"
  #include "nvim/main.h"
  #include "nvim/ui_client.h"
  #include "nvim/vim.h"
  #ifdef HAVE_LOCALE_H
  # include <locale.h>
  #endif
  #include "nvim/garray.h"
  #include "nvim/log.h"
  #include "nvim/mark.h"
  #include "nvim/mbyte.h"
  #include "nvim/memline.h"
  #include "nvim/memory.h"
  #include "nvim/message.h"
  #include "nvim/mouse.h"
  #include "nvim/move.h"
  #include "nvim/normal.h"
  #include "nvim/ops.h"
  #include "nvim/option.h"
  #include "nvim/os/fileio.h"
  #include "nvim/os/input.h"
  #include "nvim/os/os.h"
  #include "nvim/os/os_defs.h"
  #include "nvim/os/time.h"
  #include "nvim/os_unix.h"
  #include "nvim/path.h"
  #include "nvim/popupmnu.h"
  #include "nvim/profile.h"
  #include "nvim/quickfix.h"
  #include "nvim/screen.h"
  #include "nvim/shada.h"
  #include "nvim/sign.h"
  #include "nvim/state.h"
  #include "nvim/strings.h"
  #include "nvim/syntax.h"
  #include "nvim/ui.h"
  #include "nvim/ui_compositor.h"
  #include "nvim/version.h"
  #include "nvim/window.h"
  #ifdef WIN32
  # include "nvim/os/os_win_console.h"
  #endif
  #include "nvim/api/private/defs.h"
  #include "nvim/api/private/dispatch.h"
  #include "nvim/api/private/helpers.h"
  #include "nvim/api/ui.h"
  #include "nvim/event/loop.h"
  #include "nvim/event/process.h"
  #include "nvim/msgpack_rpc/channel.h"
  #include "nvim/msgpack_rpc/helpers.h"
  #include "nvim/msgpack_rpc/server.h"
  #include "nvim/os/signal.h"
  #ifndef WIN32
  # include "nvim/os/pty_process_unix.h"
  #endif
  #include "nvim/api/extmark.h"
  
  // values for "window_layout"
  #define WIN_HOR     1       // "-o" horizontally split windows
  #define WIN_VER     2       // "-O" vertically split windows
  #define WIN_TABS    3       // "-p" windows on tab pages
  
  // Values for edit_type.
  #define EDIT_NONE   0       // no edit type yet
  #define EDIT_FILE   1       // file name argument[s] given, use argument list
  #define EDIT_STDIN  2       // read file from stdin
  #define EDIT_TAG    3       // tag name argument given, use tagname
  #define EDIT_QF     4       // start in quickfix mode
  
  #ifdef INCLUDE_GENERATED_DECLARATIONS
  # include "main.c.generated.h"
  #endif
  
  Loop main_loop;
  
  static char *argv0 = NULL;
  
  // Error messages
  static const char *err_arg_missing = N_("Argument missing after");
  static const char *err_opt_garbage = N_("Garbage after option argument");
  static const char *err_opt_unknown = N_("Unknown option argument");
  static const char *err_too_many_args = N_("Too many edit arguments");
  static const char *err_extra_cmd =
    N_("Too many \"+command\", \"-c command\" or \"--cmd command\" arguments");
  
  void event_init(void)
  {
    loop_init(&main_loop, NULL);
    resize_events = multiqueue_new_child(main_loop.events);
  
    // early msgpack-rpc initialization
    msgpack_rpc_init_method_table();
    msgpack_rpc_helpers_init();
    input_init();
    signal_init();
    // finish mspgack-rpc initialization
    channel_init();
    terminal_init();
    ui_init();
  }
  
  /// @returns false if main_loop could not be closed gracefully
  bool event_teardown(void)
  {
    if (!main_loop.events) {
      input_stop();
      return true;
    }
  
    multiqueue_process_events(main_loop.events);
    loop_poll_events(&main_loop, 0);  // Drain thread_events, fast_events.
    input_stop();
    channel_teardown();
    process_teardown(&main_loop);
    timer_teardown();
    server_teardown();
    signal_teardown();
    terminal_teardown();
  
    return loop_close(&main_loop, true);
  }
  
  /// Performs early initialization.
  ///
  /// Needed for unit tests. Must be called after `time_init()`.
  void early_init(mparm_T *paramp)
  {
    env_init();
    cmdline_init();
    eval_init();          // init global variables
    init_path(argv0 ? argv0 : "nvim");
    init_normal_cmds();   // Init the table of Normal mode commands.
    runtime_init();
    highlight_init();
  
  #ifdef WIN32
    OSVERSIONINFO ovi;
    ovi.dwOSVersionInfoSize = sizeof(ovi);
    GetVersionEx(&ovi);
    snprintf(windowsVersion, sizeof(windowsVersion), "%d.%d",
             (int)ovi.dwMajorVersion, (int)ovi.dwMinorVersion);
  #endif
  
  #if defined(HAVE_LOCALE_H)
    // Setup to use the current locale (for ctype() and many other things).
    // NOTE: Translated messages with encodings other than latin1 will not
    // work until set_init_1() has been called!
    init_locale();
  #endif
  
    // Allocate the first window and buffer.
    // Can't do anything without it, exit when it fails.
    if (!win_alloc_first()) {
      os_exit(0);
    }
  
    init_yank();                  // init yank buffers
  
    alist_init(&global_alist);    // Init the argument list to empty.
    global_alist.id = 0;
  
    // Set the default values for the options.
    // First find out the home directory, needed to expand "~" in options.
    init_homedir();               // find real value of $HOME
    set_init_1(paramp != NULL ? paramp->clean : false);
    log_init();
    TIME_MSG("inits 1");
  
    set_lang_var();               // set v:lang and v:ctype
  
    init_signs();
    ui_comp_syn_init();
  }
  
  #ifdef MAKE_LIB
  int nvim_main(int argc, char **argv);  // silence -Wmissing-prototypes
  int nvim_main(int argc, char **argv)
  #elif defined(WIN32)
  int wmain(int argc, wchar_t **argv_w)  // multibyte args on Windows. #7060
  #else
  int main(int argc, char **argv)
  #endif
  {
  #if defined(WIN32) && !defined(MAKE_LIB)
    char **argv = xmalloc((size_t)argc * sizeof(char *));
    for (int i = 0; i < argc; i++) {
      char *buf = NULL;
      utf16_to_utf8(argv_w[i], -1, &buf);
      assert(buf);
      argv[i] = buf;
    }
  #endif
  
    argv0 = argv[0];
  
    char_u *fname = NULL;   // file name from command line
    mparm_T params;         // various parameters passed between
                            // main() and other functions.
    char_u *cwd = NULL;     // current working dir on startup
    time_init();
  
    // Many variables are in `params` so that we can pass them around easily.
    // `argc` and `argv` are also copied, so that they can be changed.
    init_params(&params, argc, argv);
  
    // Since os_open is called during the init_startuptime, we need to call
    // fs_init before it.
    fs_init();
  
    init_startuptime(&params);
  
    // Need to find "--clean" before actually parsing arguments.
    for (int i = 1; i < params.argc; i++) {
      if (STRICMP(params.argv[i], "--clean") == 0) {
        params.clean = true;
        break;
      }
    }
  
    event_init();
  
    early_init(&params);
  
    set_argv_var(argv, argc);  // set v:argv
  
    // Check if we have an interactive window.
    check_and_set_isatty(&params);
  
    // Process the command line arguments.  File names are put in the global
    // argument list "global_alist".
    command_line_scan(&params);
  
    nlua_init();
  
    if (embedded_mode) {
      const char *err;
      if (!channel_from_stdio(true, CALLBACK_READER_INIT, &err)) {
        abort();
      }
    }
  
    server_init(params.listen_addr);
    if (params.remote) {
      remote_request(&params, params.remote, params.server_addr, argc, argv);
    }
  
    if (GARGCOUNT > 0) {
      fname = get_fname(&params, cwd);
    }
  
    // Recovery mode without a file name: List swap files.
    // In this case, no UI is needed.
    if (recoverymode && fname == NULL) {
      headless_mode = true;
    }
  
    TIME_MSG("expanding arguments");
  
    if (params.diff_mode && params.window_count == -1) {
      params.window_count = 0;            // open up to 3 windows
    }
    // Don't redraw until much later.
    RedrawingDisabled++;
  
    setbuf(stdout, NULL);
  
    full_screen = !silent_mode;
  
    // Set the default values for the options that use Rows and Columns.
    win_init_size();
    // Set the 'diff' option now, so that it can be checked for in a vimrc
    // file.  There is no buffer yet though.
    if (params.diff_mode) {
      diff_win_options(firstwin, false);
    }
  
    assert(p_ch >= 0 && Rows >= p_ch && Rows - p_ch <= INT_MAX);
    cmdline_row = (int)(Rows - p_ch);
    msg_row = cmdline_row;
    screenalloc();  // allocate screen buffers
    set_init_2(headless_mode);
    TIME_MSG("inits 2");
  
    msg_scroll = true;
    no_wait_return = true;
  
    init_highlight(true, false);  // Default highlight groups.
    TIME_MSG("init highlight");
  
    // Set the break level after the terminal is initialized.
    debug_break_level = params.use_debug_break_level;
  
    // Read ex-commands if invoked with "-es".
    if (!params.input_isatty && !params.input_neverscript
        && silent_mode && exmode_active) {
      input_start(STDIN_FILENO);
    }
  
    // Wait for UIs to set up Nvim or show early messages
    // and prompts (--cmd, swapfile dialog, …).
    bool use_remote_ui = (embedded_mode && !headless_mode);
    bool use_builtin_ui = (!headless_mode && !embedded_mode && !silent_mode);
    if (use_remote_ui || use_builtin_ui) {
      TIME_MSG("waiting for UI");
      if (use_remote_ui) {
        remote_ui_wait_for_attach();
      } else {
        ui_builtin_start();
      }
      TIME_MSG("done waiting for UI");
  
      // prepare screen now, so external UIs can display messages
      starting = NO_BUFFERS;
      screenclear();
      TIME_MSG("init screen for UI");
    }
  
    if (ui_client_channel_id) {
      ui_client_init(ui_client_channel_id);
      ui_client_execute(ui_client_channel_id);
      abort();  // unreachable
    }
  
    init_default_mappings();  // Default mappings.
    TIME_MSG("init default mappings");
  
    init_default_autocmds();
    TIME_MSG("init default autocommands");
  
    bool vimrc_none = params.use_vimrc != NULL && strequal(params.use_vimrc, "NONE");
  
    // Reset 'loadplugins' for "-u NONE" before "--cmd" arguments.
    // Allows for setting 'loadplugins' there.
    if (vimrc_none) {
      // When using --clean we still want to load plugins
      p_lpl = params.clean;
    }
  
    // Execute --cmd arguments.
    exe_pre_commands(&params);
  
    if (!vimrc_none || params.clean) {
      // Sources ftplugin.vim and indent.vim. We do this *before* the user startup scripts to ensure
      // ftplugins run before FileType autocommands defined in the init file (which allows those
      // autocommands to overwrite settings from ftplugins).
      filetype_plugin_enable();
    }
  
    // Source startup scripts.
    source_startup_scripts(&params);
  
    // If using the runtime (-u is not NONE), enable syntax & filetype plugins.
    if (!vimrc_none || params.clean) {
      // Sources filetype.lua and filetype.vim unless the user explicitly disabled it with :filetype
      // off.
      filetype_maybe_enable();
      // Sources syntax/syntax.vim. We do this *after* the user startup scripts so that users can
      // disable syntax highlighting with `:syntax off` if they wish.
      syn_maybe_enable();
    }
  
    // Read all the plugin files.
    load_plugins();
  
    // Decide about window layout for diff mode after reading vimrc.
    set_window_layout(&params);
  
    // Recovery mode without a file name: List swap files.
    // Uses the 'dir' option, therefore it must be after the initializations.
    if (recoverymode && fname == NULL) {
      recover_names(NULL, true, 0, NULL);
      os_exit(0);
    }
  
    // Set some option defaults after reading vimrc files.
    set_init_3();
    TIME_MSG("inits 3");
  
    // "-n" argument: Disable swap file by setting 'updatecount' to 0.
    // Note that this overrides anything from a vimrc file.
    if (params.no_swap_file) {
      p_uc = 0;
    }
  
    // XXX: Minimize 'updatetime' for -es/-Es. #7679
    if (silent_mode) {
      p_ut = 1;
    }
  
    //
    // Read in registers, history etc, from the ShaDa file.
    // This is where v:oldfiles gets filled.
    //
    if (*p_shada != NUL) {
      shada_read_everything(NULL, false, true);
      TIME_MSG("reading ShaDa");
    }
    // It's better to make v:oldfiles an empty list than NULL.
    if (get_vim_var_list(VV_OLDFILES) == NULL) {
      set_vim_var_list(VV_OLDFILES, tv_list_alloc(0));
    }
  
    // "-q errorfile": Load the error file now.
    // If the error file can't be read, exit before doing anything else.
    handle_quickfix(&params);
  
    //
    // Start putting things on the screen.
    // Scroll screen down before drawing over it
    // Clear screen now, so file message will not be cleared.
    //
    starting = NO_BUFFERS;
    no_wait_return = false;
    if (!exmode_active) {
      msg_scroll = false;
    }
  
    // Read file (text, not commands) from stdin if:
    //    - stdin is not a tty
    //    - and -e/-es was not given
    //
    // Do this before starting Raw mode, because it may change things that the
    // writing end of the pipe doesn't like, e.g., in case stdin and stderr
    // are the same terminal: "cat | vim -".
    // Using autocommands here may cause trouble...
    if (params.edit_type == EDIT_STDIN && !recoverymode) {
      read_stdin();
    }
  
    setmouse();  // may start using the mouse
  
    if (exmode_active || use_remote_ui || use_builtin_ui) {
      // Don't clear the screen when starting in Ex mode, or when a UI might have
      // displayed messages.
      redraw_later(curwin, VALID);
    } else {
      screenclear();  // clear screen
      TIME_MSG("clearing screen");
    }
  
    no_wait_return = true;
  
    //
    // Create the requested number of windows and edit buffers in them.
    // Also does recovery if "recoverymode" set.
    //
    create_windows(&params);
    TIME_MSG("opening buffers");
  
    // Clear v:swapcommand
    set_vim_var_string(VV_SWAPCOMMAND, NULL, -1);
  
    // Ex starts at last line of the file.
    if (exmode_active) {
      curwin->w_cursor.lnum = curbuf->b_ml.ml_line_count;
    }
  
    apply_autocmds(EVENT_BUFENTER, NULL, NULL, false, curbuf);
    TIME_MSG("BufEnter autocommands");
    setpcmark();
  
    // When started with "-q errorfile" jump to first error now.
    if (params.edit_type == EDIT_QF) {
      qf_jump(NULL, 0, 0, FALSE);
      TIME_MSG("jump to first error");
    }
  
    // If opened more than one window, start editing files in the other
    // windows.
    edit_buffers(&params, cwd);
    xfree(cwd);
  
    if (params.diff_mode) {
      // set options in each window for "nvim -d".
      FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
        diff_win_options(wp, TRUE);
      }
    }
  
    // Shorten any of the filenames, but only when absolute.
    shorten_fnames(false);
  
    // Need to jump to the tag before executing the '-c command'.
    // Makes "vim -c '/return' -t main" work.
    handle_tag(params.tagname);
  
    // Execute any "+", "-c" and "-S" arguments.
    if (params.n_commands > 0) {
      exe_commands(&params);
    }
  
    starting = 0;
  
    RedrawingDisabled = 0;
    redraw_all_later(NOT_VALID);
    no_wait_return = false;
  
    // 'autochdir' has been postponed.
    do_autochdir();
  
    // start in insert mode
    if (p_im) {
      need_start_insertmode = true;
    }
  
    set_vim_var_nr(VV_VIM_DID_ENTER, 1L);
    apply_autocmds(EVENT_VIMENTER, NULL, NULL, false, curbuf);
    TIME_MSG("VimEnter autocommands");
    if (use_remote_ui || use_builtin_ui) {
      do_autocmd_uienter(use_remote_ui ? CHAN_STDIO : 0, true);
      TIME_MSG("UIEnter autocommands");
    }
  
    // Adjust default register name for "unnamed" in 'clipboard'. Can only be
    // done after the clipboard is available and all initial commands that may
    // modify the 'clipboard' setting have run; i.e. just before entering the
    // main loop.
    set_reg_var(get_default_register_name());
  
    // When a startup script or session file setup for diff'ing and
    // scrollbind, sync the scrollbind now.
    if (curwin->w_p_diff && curwin->w_p_scb) {
      update_topline(curwin);
      check_scrollbind((linenr_T)0, 0L);
      TIME_MSG("diff scrollbinding");
    }
  
    // If ":startinsert" command used, stuff a dummy command to be able to
    // call normal_cmd(), which will then start Insert mode.
    if (restart_edit != 0) {
      stuffcharReadbuff(K_NOP);
    }
  
    // WORKAROUND(mhi): #3023
    if (cb_flags & CB_UNNAMEDMASK) {
      (void)eval_has_provider("clipboard");
    }
  
    TIME_MSG("before starting main loop");
    ILOG("starting main loop");
  
    // Main loop: never returns.
    normal_enter(false, false);
  
  #if defined(WIN32) && !defined(MAKE_LIB)
    xfree(argv);
  #endif
    return 0;
  }
  
  void os_exit(int r)
    FUNC_ATTR_NORETURN
  {
    exiting = true;
  
    ui_flush();
    ui_call_stop();
    ml_close_all(true);           // remove all memfiles
  
    if (!event_teardown() && r == 0) {
      r = 1;  // Exit with error if main_loop did not teardown gracefully.
    }
    if (input_global_fd() >= 0) {
      stream_set_blocking(input_global_fd(), true);  // normalize stream (#2598)
    }
  
    ILOG("Nvim exit: %d", r);
  
  #ifdef EXITFREE
    free_all_mem();
  #endif
  
    exit(r);
  }
  
  /// Exit properly
  void getout(int exitval)
    FUNC_ATTR_NORETURN
  {
    exiting = true;
  
    // When running in Ex mode an error causes us to exit with a non-zero exit
    // code.  POSIX requires this, although it's not 100% clear from the
    // standard.
    if (exmode_active) {
      exitval += ex_exitval;
    }
  
    set_vim_var_nr(VV_EXITING, exitval);
  
    // Position the cursor on the last screen line, below all the text
    ui_cursor_goto(Rows - 1, 0);
  
    // Optionally print hashtable efficiency.
    hash_debug_results();
  
    if (v_dying <= 1) {
      const tabpage_T *next_tp;
  
      // Trigger BufWinLeave for all windows, but only once per buffer.
      for (const tabpage_T *tp = first_tabpage; tp != NULL; tp = next_tp) {
        next_tp = tp->tp_next;
        FOR_ALL_WINDOWS_IN_TAB(wp, tp) {
          if (wp->w_buffer == NULL) {
            // Autocmd must have close the buffer already, skip.
            continue;
          }
  
          buf_T *buf = wp->w_buffer;
          if (buf_get_changedtick(buf) != -1) {
            bufref_T bufref;
  
            set_bufref(&bufref, buf);
            apply_autocmds(EVENT_BUFWINLEAVE, buf->b_fname,
                           buf->b_fname, false, buf);
            if (bufref_valid(&bufref)) {
              buf_set_changedtick(buf, -1);  // note that we did it already
            }
            // start all over, autocommands may mess up the lists
            next_tp = first_tabpage;
            break;
          }
        }
      }
  
      // Trigger BufUnload for buffers that are loaded
      FOR_ALL_BUFFERS(buf) {
        if (buf->b_ml.ml_mfp != NULL) {
          bufref_T bufref;
          set_bufref(&bufref, buf);
          apply_autocmds(EVENT_BUFUNLOAD, buf->b_fname, buf->b_fname, false, buf);
          if (!bufref_valid(&bufref)) {
            // Autocmd deleted the buffer.
            break;
          }
        }
      }
  
      int unblock = 0;
      // deathtrap() blocks autocommands, but we do want to trigger
      // VimLeavePre.
      if (is_autocmd_blocked()) {
        unblock_autocmds();
        unblock++;
      }
      apply_autocmds(EVENT_VIMLEAVEPRE, NULL, NULL, false, curbuf);
      if (unblock) {
        block_autocmds();
      }
    }
  
    if (p_shada && *p_shada != NUL) {
      // Write out the registers, history, marks etc, to the ShaDa file
      shada_write_file(NULL, false);
    }
  
    if (v_dying <= 1) {
      int unblock = 0;
  
      // deathtrap() blocks autocommands, but we do want to trigger VimLeave.
      if (is_autocmd_blocked()) {
        unblock_autocmds();
        unblock++;
      }
      apply_autocmds(EVENT_VIMLEAVE, NULL, NULL, false, curbuf);
      if (unblock) {
        block_autocmds();
      }
    }
  
    profile_dump();
  
    if (did_emsg) {
      // give the user a chance to read the (error) message
      no_wait_return = FALSE;
      wait_return(FALSE);
    }
  
    // Position the cursor again, the autocommands may have moved it
    ui_cursor_goto(Rows - 1, 0);
  
    // Apply 'titleold'.
    if (p_title && *p_titleold != NUL) {
      ui_call_set_title(cstr_as_string((char *)p_titleold));
    }
  
    cs_end();
    if (garbage_collect_at_exit) {
      garbage_collect(false);
    }
  
    os_exit(exitval);
  }
  
  /// Preserve files and exit.
  /// @note IObuff must contain a message.
  /// @note This may be called from deadly_signal() in a signal handler, avoid
  ///       unsafe functions, such as allocating memory.
  void preserve_exit(void)
    FUNC_ATTR_NORETURN
  {
    // 'true' when we are sure to exit, e.g., after a deadly signal
    static bool really_exiting = false;
  
    // Prevent repeated calls into this method.
    if (really_exiting) {
      if (input_global_fd() >= 0) {
        // normalize stream (#2598)
        stream_set_blocking(input_global_fd(), true);
      }
      exit(2);
    }
  
    really_exiting = true;
    // Ignore SIGHUP while we are already exiting. #9274
    signal_reject_deadly();
    mch_errmsg(IObuff);
    mch_errmsg("\n");
    ui_flush();
  
    ml_close_notmod();                // close all not-modified buffers
  
    FOR_ALL_BUFFERS(buf) {
      if (buf->b_ml.ml_mfp != NULL && buf->b_ml.ml_mfp->mf_fname != NULL) {
        mch_errmsg("Vim: preserving files...\r\n");
        ui_flush();
        ml_sync_all(false, false, true);  // preserve all swap files
        break;
      }
    }
  
    ml_close_all(false);              // close all memfiles, without deleting
  
    mch_errmsg("Vim: Finished.\r\n");
  
    getout(1);
  }
  
  /// Gets the integer value of a numeric command line argument if given,
  /// such as '-o10'.
  ///
  /// @param[in] p         pointer to argument
  /// @param[in, out] idx  pointer to index in argument, is incremented
  /// @param[in] def       default value
  ///
  /// @return def unmodified if:
  ///   - argument isn't given
  ///   - argument is non-numeric
  ///
  /// @return argument's numeric value otherwise
  static int get_number_arg(const char *p, int *idx, int def)
    FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT
  {
    if (ascii_isdigit(p[*idx])) {  // -V522
      def = atoi(&(p[*idx]));
      while (ascii_isdigit(p[*idx])) {
        *idx = *idx + 1;
      }
    }
    return def;
  }
  
  #if defined(HAVE_LOCALE_H)
  /// Setup to use the current locale (for ctype() and many other things).
  static void init_locale(void)
  {
    setlocale(LC_ALL, "");
  
  # ifdef LC_NUMERIC
    // Make sure strtod() uses a decimal point, not a comma.
    setlocale(LC_NUMERIC, "C");
  # endif
  
    char localepath[MAXPATHL] = { 0 };
    snprintf(localepath, sizeof(localepath), "%s", get_vim_var_str(VV_PROGPATH));
    char *tail = (char *)path_tail_with_sep((char_u *)localepath);
    *tail = NUL;
    tail = (char *)path_tail((char_u *)localepath);
    xstrlcpy(tail, "share/locale",
             sizeof(localepath) - (size_t)(tail - localepath));
    bindtextdomain(PROJECT_NAME, localepath);
    textdomain(PROJECT_NAME);
    TIME_MSG("locale set");
  }
  #endif
  
  
  static uint64_t server_connect(char *server_addr, const char **errmsg)
  {
    if (server_addr == NULL) {
      *errmsg = "no address specified";
      return 0;
    }
    CallbackReader on_data = CALLBACK_READER_INIT;
    const char *error = NULL;
    bool is_tcp = strrchr(server_addr, ':') ? true : false;
    // connected to channel
    uint64_t chan = channel_connect(is_tcp, server_addr, true, on_data, 50, &error);
    if (error) {
      *errmsg = error;
      return 0;
    }
    return chan;
  }
  
  /// Handle remote subcommands
  static void remote_request(mparm_T *params, int remote_args,
                             char *server_addr, int argc, char **argv)
  {
    const char *connect_error = NULL;
    uint64_t chan = server_connect(server_addr, &connect_error);
    Object rvobj = OBJECT_INIT;
  
    if (strequal(argv[remote_args], "--remote-ui-test")) {
      if (!chan) {
        emsg(connect_error);
        exit(1);
      }
  
      ui_client_channel_id = chan;
      return;
    }
  
    Array args = ARRAY_DICT_INIT;
    String arg_s;
    for (int t_argc = remote_args; t_argc < argc; t_argc++) {
      arg_s = cstr_to_string(argv[t_argc]);
      ADD(args, STRING_OBJ(arg_s));
    }
  
    Error err = ERROR_INIT;
    Array a = ARRAY_DICT_INIT;
    ADD(a, INTEGER_OBJ((int)chan));
    ADD(a, CSTR_TO_OBJ(server_addr));
    ADD(a, CSTR_TO_OBJ(connect_error));
    ADD(a, ARRAY_OBJ(args));
    String s = STATIC_CSTR_AS_STRING("return vim._cs_remote(...)");
    Object o = nlua_exec(s, a, &err);
    api_free_array(a);
    if (ERROR_SET(&err)) {
      mch_errmsg(err.msg);
      mch_errmsg("\n");
      os_exit(2);
    }
  
    if (o.type == kObjectTypeDictionary) {
      rvobj.data.dictionary = o.data.dictionary;
    } else {
      mch_errmsg("vim._cs_remote returned unexpected value\n");
      os_exit(2);
    }
  
    TriState should_exit = kNone;
    TriState tabbed = kNone;
  
    for (size_t i = 0; i < rvobj.data.dictionary.size ; i++) {
      if (strcmp(rvobj.data.dictionary.items[i].key.data, "errmsg") == 0) {
        if (rvobj.data.dictionary.items[i].value.type != kObjectTypeString) {
          mch_errmsg("vim._cs_remote returned an unexpected type for 'errmsg'\n");
          os_exit(2);
        }
        mch_errmsg(rvobj.data.dictionary.items[i].value.data.string.data);
        mch_errmsg("\n");
        os_exit(2);
      } else if (strcmp(rvobj.data.dictionary.items[i].key.data, "tabbed") == 0) {
        if (rvobj.data.dictionary.items[i].value.type != kObjectTypeBoolean) {
          mch_errmsg("vim._cs_remote returned an unexpected type for 'tabbed'\n");
          os_exit(2);
        }
        tabbed = rvobj.data.dictionary.items[i].value.data.boolean ? kTrue : kFalse;
      } else if (strcmp(rvobj.data.dictionary.items[i].key.data, "should_exit") == 0) {
        if (rvobj.data.dictionary.items[i].value.type != kObjectTypeBoolean) {
          mch_errmsg("vim._cs_remote returned an unexpected type for 'should_exit'\n");
          os_exit(2);
        }
        should_exit = rvobj.data.dictionary.items[i].value.data.boolean ? kTrue : kFalse;
      }
    }
    if (should_exit == kNone || tabbed == kNone) {
      mch_errmsg("vim._cs_remote didn't return a value for should_exit or tabbed, bailing\n");
      os_exit(2);
    }
    api_free_object(o);
  
    if (should_exit == kTrue) {
      os_exit(0);
    }
    if (tabbed == kTrue) {
      params->window_count = argc - remote_args - 1;
      params->window_layout = WIN_TABS;
    }
  }
  
  
  /// Decides whether text (as opposed to commands) will be read from stdin.
  /// @see EDIT_STDIN
  static bool edit_stdin(bool explicit, mparm_T *parmp)
  {
    bool implicit = !headless_mode
                    && !embedded_mode
                    && (!exmode_active || parmp->input_neverscript)
                    && !parmp->input_isatty
                    && scriptin[0] == NULL;  // `-s -` was not given.
    return explicit || implicit;
  }
  
  /// Scan the command line arguments.
  static void command_line_scan(mparm_T *parmp)
  {
    int argc = parmp->argc;
    char **argv = parmp->argv;
    int argv_idx;                         // index in argv[n][]
    bool had_stdin_file = false;          // found explicit "-" argument
    bool had_minmin = false;              // found "--" argument
    int want_argument;                    // option argument with argument
    long n;
  
    argc--;
    argv++;
    argv_idx = 1;  // active option letter is argv[0][argv_idx]
    while (argc > 0) {
      // "+" or "+{number}" or "+/{pat}" or "+{command}" argument.
      if (argv[0][0] == '+' && !had_minmin) {
        if (parmp->n_commands >= MAX_ARG_CMDS) {
          mainerr(err_extra_cmd, NULL);
        }
        argv_idx = -1;  // skip to next argument
        if (argv[0][1] == NUL) {
          parmp->commands[parmp->n_commands++] = "$";
        } else {
          parmp->commands[parmp->n_commands++] = &(argv[0][1]);
        }
  
        // Optional argument.
      } else if (argv[0][0] == '-' && !had_minmin) {
        want_argument = false;
        char c = argv[0][argv_idx++];
        switch (c) {
        case NUL:    // "nvim -"  read from stdin
          if (exmode_active) {
            // "nvim -e -" silent mode
            silent_mode = true;
            parmp->no_swap_file = true;
          } else {
            if (parmp->edit_type != EDIT_NONE
                && parmp->edit_type != EDIT_FILE
                && parmp->edit_type != EDIT_STDIN) {
              mainerr(err_too_many_args, argv[0]);
            }
            had_stdin_file = true;
            parmp->edit_type = EDIT_STDIN;
          }
          argv_idx = -1;  // skip to next argument
          break;
        case '-':    // "--" don't take any more option arguments
          // "--help" give help message
          // "--version" give version message
          // "--noplugin[s]" skip plugins
          // "--cmd <cmd>" execute cmd before vimrc
          // "--remote" execute commands remotey on a server
          // "--server" name of vim server to send remote commands to
          if (STRICMP(argv[0] + argv_idx, "help") == 0) {
            usage();
            os_exit(0);
          } else if (STRICMP(argv[0] + argv_idx, "version") == 0) {
            version();
            os_exit(0);
          } else if (STRICMP(argv[0] + argv_idx, "api-info") == 0) {
            FileDescriptor fp;
            const int fof_ret = file_open_fd(&fp, STDOUT_FILENO,
                                             kFileWriteOnly);
            msgpack_packer *p = msgpack_packer_new(&fp, msgpack_file_write);
  
            if (fof_ret != 0) {
              semsg(_("E5421: Failed to open stdin: %s"), os_strerror(fof_ret));
            }
  
            if (p == NULL) {
              emsg(_(e_outofmem));
            }
  
            Object md = DICTIONARY_OBJ(api_metadata());
            msgpack_rpc_from_object(md, p);
  
            msgpack_packer_free(p);
            const int ff_ret = file_flush(&fp);
            if (ff_ret < 0) {
              msgpack_file_write_error(ff_ret);
            }
            os_exit(0);
          } else if (STRICMP(argv[0] + argv_idx, "headless") == 0) {
            headless_mode = true;
          } else if (STRICMP(argv[0] + argv_idx, "embed") == 0) {
            embedded_mode = true;
          } else if (STRNICMP(argv[0] + argv_idx, "listen", 6) == 0) {
            want_argument = true;
            argv_idx += 6;
          } else if (STRNICMP(argv[0] + argv_idx, "literal", 7) == 0) {
            // Do nothing: file args are always literal. #7679
          } else if (STRNICMP(argv[0] + argv_idx, "remote", 6) == 0) {
            parmp->remote = parmp->argc - argc;
          } else if (STRNICMP(argv[0] + argv_idx, "server", 6) == 0) {
            want_argument = true;
            argv_idx += 6;
          } else if (STRNICMP(argv[0] + argv_idx, "noplugin", 8) == 0) {
            p_lpl = false;
          } else if (STRNICMP(argv[0] + argv_idx, "cmd", 3) == 0) {
            want_argument = true;
            argv_idx += 3;
          } else if (STRNICMP(argv[0] + argv_idx, "startuptime", 11) == 0) {
            want_argument = true;
            argv_idx += 11;
          } else if (STRNICMP(argv[0] + argv_idx, "clean", 5) == 0) {
            parmp->use_vimrc = "NONE";
            parmp->clean = true;
            set_option_value("shadafile", 0L, "NONE", 0);
          } else if (STRNICMP(argv[0] + argv_idx, "luamod-dev", 9) == 0) {
            nlua_disable_preload = true;
          } else {
            if (argv[0][argv_idx]) {
              mainerr(err_opt_unknown, argv[0]);
            }
            had_minmin = true;
          }
          if (!want_argument) {
            argv_idx = -1;  // skip to next argument
          }
          break;
        case 'A':    // "-A" start in Arabic mode.
          set_option_value("arabic", 1L, NULL, 0);
          break;
        case 'b':    // "-b" binary mode.
          // Needs to be effective before expanding file names, because
          // for Win32 this makes us edit a shortcut file itself,
          // instead of the file it links to.
          set_options_bin(curbuf->b_p_bin, 1, 0);
          curbuf->b_p_bin = 1;  // Binary file I/O.
          break;
  
        case 'D':    // "-D" Debugging
          parmp->use_debug_break_level = 9999;
          break;
        case 'd':    // "-d" 'diff'
          parmp->diff_mode = true;
          break;
        case 'e':    // "-e" Ex mode
          exmode_active = true;
          break;
        case 'E':    // "-E" Ex mode
          exmode_active = true;
          parmp->input_neverscript = true;
          break;
        case 'f':    // "-f"  GUI: run in foreground.
          break;
        case '?':    // "-?" give help message (for MS-Windows)
        case 'h':    // "-h" give help message
          usage();
          os_exit(0);
        case 'H':    // "-H" start in Hebrew mode: rl + hkmap set.
          p_hkmap = true;
          set_option_value("rl", 1L, NULL, 0);
          break;
        case 'l':    // "-l" lisp mode, 'lisp' and 'showmatch' on.
          set_option_value("lisp", 1L, NULL, 0);
          p_sm = true;
          break;
        case 'M':    // "-M"  no changes or writing of files
          reset_modifiable();
          FALLTHROUGH;
        case 'm':    // "-m"  no writing of files
          p_write = false;
          break;
  
        case 'N':    // "-N"  Nocompatible
        case 'X':    // "-X"  Do not connect to X server
          // No-op
          break;
  
        case 'n':    // "-n" no swap file
          parmp->no_swap_file = true;
          break;
        case 'p':    // "-p[N]" open N tab pages
          // default is 0: open window for each file
          parmp->window_count = get_number_arg(argv[0], &argv_idx, 0);
          parmp->window_layout = WIN_TABS;
          break;
        case 'o':    // "-o[N]" open N horizontal split windows
          // default is 0: open window for each file
          parmp->window_count = get_number_arg(argv[0], &argv_idx, 0);
          parmp->window_layout = WIN_HOR;
          break;
        case 'O':    // "-O[N]" open N vertical split windows
          // default is 0: open window for each file
          parmp->window_count = get_number_arg(argv[0], &argv_idx, 0);
          parmp->window_layout = WIN_VER;
          break;
        case 'q':    // "-q" QuickFix mode
          if (parmp->edit_type != EDIT_NONE) {
            mainerr(err_too_many_args, argv[0]);
          }
          parmp->edit_type = EDIT_QF;
          if (argv[0][argv_idx]) {  // "-q{errorfile}"
            parmp->use_ef = (char_u *)argv[0] + argv_idx;
            argv_idx = -1;
          } else if (argc > 1) {    // "-q {errorfile}"
            want_argument = true;
          }
          break;
        case 'R':    // "-R" readonly mode
          readonlymode = true;
          curbuf->b_p_ro = true;
          p_uc = 10000;  // don't update very often
          break;
        case 'r':    // "-r" recovery mode
        case 'L':    // "-L" recovery mode
          recoverymode = 1;
          break;
        case 's':
          if (exmode_active) {    // "-es" silent (batch) Ex-mode
            silent_mode = true;
            parmp->no_swap_file = true;
          } else {                // "-s {scriptin}" read from script file
            want_argument = true;
          }
          break;
        case 't':    // "-t {tag}" or "-t{tag}" jump to tag
          if (parmp->edit_type != EDIT_NONE) {
            mainerr(err_too_many_args, argv[0]);
          }
          parmp->edit_type = EDIT_TAG;
          if (argv[0][argv_idx]) {  // "-t{tag}"
            parmp->tagname = (char_u *)argv[0] + argv_idx;
            argv_idx = -1;
          } else {  // "-t {tag}"
            want_argument = true;
          }
          break;
        case 'v':
          version();
          os_exit(0);
        case 'V':    // "-V{N}" Verbose level
          // default is 10: a little bit verbose
          p_verbose = get_number_arg(argv[0], &argv_idx, 10);
          if (argv[0][argv_idx] != NUL) {
            set_option_value("verbosefile", 0L, argv[0] + argv_idx, 0);
            argv_idx = (int)STRLEN(argv[0]);
          }
          break;
        case 'w':    // "-w{number}" set window height
          // "-w {scriptout}" write to script
          if (ascii_isdigit(((char_u *)argv[0])[argv_idx])) {
            n = get_number_arg(argv[0], &argv_idx, 10);
            set_option_value("window", n, NULL, 0);
            break;
          }
          want_argument = true;
          break;
  
        case 'c':    // "-c{command}" or "-c {command}" exec command
          if (argv[0][argv_idx] != NUL) {
            if (parmp->n_commands >= MAX_ARG_CMDS) {
              mainerr(err_extra_cmd, NULL);
            }
            parmp->commands[parmp->n_commands++] = argv[0] + argv_idx;
            argv_idx = -1;
            break;
          }
          FALLTHROUGH;
        case 'S':    // "-S {file}" execute Vim script
        case 'i':    // "-i {shada}" use for ShaDa file
        case 'u':    // "-u {vimrc}" vim inits file
        case 'U':    // "-U {gvimrc}" gvim inits file
        case 'W':    // "-W {scriptout}" overwrite
          want_argument = true;
          break;
  
        default:
          mainerr(err_opt_unknown, argv[0]);
        }
  
        // Handle option arguments with argument.
        if (want_argument) {
          // Check for garbage immediately after the option letter.
          if (argv[0][argv_idx] != NUL) {
            mainerr(err_opt_garbage, argv[0]);
          }
  
          argc--;
          if (argc < 1 && c != 'S') {  // -S has an optional argument
            mainerr(err_arg_missing, argv[0]);
          }
          argv++;
          argv_idx = -1;
  
          switch (c) {
          case 'c':    // "-c {command}" execute command
          case 'S':    // "-S {file}" execute Vim script
            if (parmp->n_commands >= MAX_ARG_CMDS) {
              mainerr(err_extra_cmd, NULL);
            }
            if (c == 'S') {
              char *a;
  
              if (argc < 1) {
                // "-S" without argument: use default session file name.
                a = SESSION_FILE;
              } else if (argv[0][0] == '-') {
                // "-S" followed by another option: use default session file.
                a = SESSION_FILE;
                ++argc;
                --argv;
              } else {
                a = argv[0];
              }
  
              size_t s_size = STRLEN(a) + 9;
              char *s = xmalloc(s_size);
              snprintf(s, s_size, "so %s", a);
              parmp->cmds_tofree[parmp->n_commands] = true;
              parmp->commands[parmp->n_commands++] = s;
            } else {
              parmp->commands[parmp->n_commands++] = argv[0];
            }
            break;
  
          case '-':
            if (strequal(argv[-1], "--cmd")) {
              // "--cmd {command}" execute command
              if (parmp->n_pre_commands >= MAX_ARG_CMDS) {
                mainerr(err_extra_cmd, NULL);
              }
              parmp->pre_commands[parmp->n_pre_commands++] = argv[0];
            } else if (strequal(argv[-1], "--listen")) {
              // "--listen {address}"
              parmp->listen_addr = argv[0];
            } else if (strequal(argv[-1], "--server")) {
              // "--server {address}"
              parmp->server_addr = argv[0];
            }
            // "--startuptime <file>" already handled
            break;
  
          case 'q':    // "-q {errorfile}" QuickFix mode
            parmp->use_ef = (char_u *)argv[0];
            break;
  
          case 'i':    // "-i {shada}" use for shada
            set_option_value("shadafile", 0L, argv[0], 0);
            break;
  
          case 's': {  // "-s {scriptin}" read from script file
            if (scriptin[0] != NULL) {
  scripterror:
              vim_snprintf((char *)IObuff, IOSIZE,
                           _("Attempt to open script file again: \"%s %s\"\n"),
                           argv[-1], argv[0]);
              mch_errmsg((const char *)IObuff);
              os_exit(2);
            }
            int error;
            if (strequal(argv[0], "-")) {
              const int stdin_dup_fd = os_dup(STDIN_FILENO);
  #ifdef WIN32
              // Replace the original stdin with the console input handle.
              os_replace_stdin_to_conin();
  #endif
              FileDescriptor *const stdin_dup = file_open_fd_new(&error, stdin_dup_fd,
                                                                 kFileReadOnly|kFileNonBlocking);
              assert(stdin_dup != NULL);
              scriptin[0] = stdin_dup;
            } else if ((scriptin[0] =
                          file_open_new(&error, argv[0], kFileReadOnly|kFileNonBlocking,
                                        0)) == NULL) {
              vim_snprintf((char *)IObuff, IOSIZE,
                           _("Cannot open for reading: \"%s\": %s\n"),
                           argv[0], os_strerror(error));
              mch_errmsg((const char *)IObuff);
              os_exit(2);
            }
            save_typebuf();
            break;
          }
  
          case 't':    // "-t {tag}"
            parmp->tagname = (char_u *)argv[0];
            break;
          case 'u':    // "-u {vimrc}" vim inits file
            parmp->use_vimrc = argv[0];
            break;
          case 'U':    // "-U {gvimrc}" gvim inits file
            break;
  
          case 'w':    // "-w {nr}" 'window' value
            // "-w {scriptout}" append to script file
            if (ascii_isdigit(*((char_u *)argv[0]))) {
              argv_idx = 0;
              n = get_number_arg(argv[0], &argv_idx, 10);
              set_option_value("window", n, NULL, 0);
              argv_idx = -1;
              break;
            }
            FALLTHROUGH;
          case 'W':    // "-W {scriptout}" overwrite script file
            if (scriptout != NULL) {
              goto scripterror;
            }
            if ((scriptout = os_fopen(argv[0], c == 'w' ? APPENDBIN : WRITEBIN))
                == NULL) {
              mch_errmsg(_("Cannot open for script output: \""));
              mch_errmsg(argv[0]);
              mch_errmsg("\"\n");
              os_exit(2);
            }
            break;
          }
        }
      } else {  // File name argument.
        argv_idx = -1;  // skip to next argument
  
        // Check for only one type of editing.
        if (parmp->edit_type != EDIT_NONE
            && parmp->edit_type != EDIT_FILE
            && parmp->edit_type != EDIT_STDIN) {
          mainerr(err_too_many_args, argv[0]);
        }
        parmp->edit_type = EDIT_FILE;
  
        // Add the file to the global argument list.
        ga_grow(&global_alist.al_ga, 1);
        char_u *p = vim_strsave((char_u *)argv[0]);
  
        if (parmp->diff_mode && os_isdir(p) && GARGCOUNT > 0
            && !os_isdir(alist_name(&GARGLIST[0]))) {
          char_u *r = (char_u *)concat_fnames((char *)p,
                                              (char *)path_tail(alist_name(&GARGLIST[0])), true);
          xfree(p);
          p = r;
        }
  
  #ifdef USE_FNAME_CASE
        // Make the case of the file name match the actual file.
        path_fix_case(p);
  #endif
  
        int alist_fnum_flag = edit_stdin(had_stdin_file, parmp)
                              ? 1   // add buffer nr after exp.
                              : 2;  // add buffer number now and use curbuf
        alist_add(&global_alist, p, alist_fnum_flag);
      }
  
      // If there are no more letters after the current "-", go to next argument.
      // argv_idx is set to -1 when the current argument is to be skipped.
      if (argv_idx <= 0 || argv[0][argv_idx] == NUL) {
        argc--;
        argv++;
        argv_idx = 1;
      }
    }
  
    if (embedded_mode && silent_mode) {
      mainerr(_("--embed conflicts with -es/-Es"), NULL);
    }
  
    // If there is a "+123" or "-c" command, set v:swapcommand to the first one.
    if (parmp->n_commands > 0) {
      const size_t swcmd_len = STRLEN(parmp->commands[0]) + 3;
      char *const swcmd = xmalloc(swcmd_len);
      snprintf(swcmd, swcmd_len, ":%s\r", parmp->commands[0]);
      set_vim_var_string(VV_SWAPCOMMAND, swcmd, -1);
      xfree(swcmd);
    }
  
    // Handle "foo | nvim". EDIT_FILE may be overwritten now. #6299
    if (edit_stdin(had_stdin_file, parmp)) {
      parmp->edit_type = EDIT_STDIN;
    }
  
    TIME_MSG("parsing arguments");
  }
  
  /*
   * Many variables are in "params" so that we can pass them to invoked
   * functions without a lot of arguments.  "argc" and "argv" are also
   * copied, so that they can be changed. */
  static void init_params(mparm_T *paramp, int argc, char **argv)
  {
    memset(paramp, 0, sizeof(*paramp));
    paramp->argc = argc;
    paramp->argv = argv;
    paramp->use_debug_break_level = -1;
    paramp->window_count = -1;
    paramp->listen_addr = NULL;
    paramp->server_addr = NULL;
    paramp->remote = 0;
  }
  
  /// Initialize global startuptime file if "--startuptime" passed as an argument.
  static void init_startuptime(mparm_T *paramp)
  {
    for (int i = 1; i < paramp->argc - 1; i++) {
      if (STRICMP(paramp->argv[i], "--startuptime") == 0) {
        time_fd = os_fopen(paramp->argv[i + 1], "a");
        time_start("--- NVIM STARTING ---");
        break;
      }
    }
  
    starttime = time(NULL);
  }
  
  static void check_and_set_isatty(mparm_T *paramp)
  {
    stdin_isatty
      = paramp->input_isatty = os_isatty(STDIN_FILENO);
    stdout_isatty
      = paramp->output_isatty = os_isatty(STDOUT_FILENO);
    paramp->err_isatty = os_isatty(STDERR_FILENO);
  #ifndef WIN32
    int tty_fd = paramp->input_isatty
      ? STDIN_FILENO
      : (paramp->output_isatty
         ? STDOUT_FILENO
         : (paramp->err_isatty ? STDERR_FILENO : -1));
    pty_process_save_termios(tty_fd);
  #endif
    TIME_MSG("window checked");
  }
  
  // Sets v:progname and v:progpath. Also modifies $PATH on Windows.
  static void init_path(const char *exename)
    FUNC_ATTR_NONNULL_ALL
  {
    char exepath[MAXPATHL] = { 0 };
    size_t exepathlen = MAXPATHL;
    // Make v:progpath absolute.
    if (os_exepath(exepath, &exepathlen) != 0) {
      // Fall back to argv[0]. Missing procfs? #6734
      path_guess_exepath(exename, exepath, sizeof(exepath));
    }
    set_vim_var_string(VV_PROGPATH, exepath, -1);
    set_vim_var_string(VV_PROGNAME, (char *)path_tail((char_u *)exename), -1);
  
  #ifdef WIN32
    // Append the process start directory to $PATH, so that ":!foo" finds tools
    // shipped with Windows package. This also mimics SearchPath().
    os_setenv_append_path(exepath);
  #endif
  }
  
  /// Get filename from command line, if any.
  static char_u *get_fname(mparm_T *parmp, char_u *cwd)
  {
    return alist_name(&GARGLIST[0]);
  }
  
  /*
   * Decide about window layout for diff mode after reading vimrc.
   */
  static void set_window_layout(mparm_T *paramp)
  {
    if (paramp->diff_mode && paramp->window_layout == 0) {
      if (diffopt_horizontal()) {
        paramp->window_layout = WIN_HOR;             // use horizontal split
      } else {
        paramp->window_layout = WIN_VER;             // use vertical split
      }
    }
  }
  
  
  /*
   * "-q errorfile": Load the error file now.
   * If the error file can't be read, exit before doing anything else.
   */
  static void handle_quickfix(mparm_T *paramp)
  {
    if (paramp->edit_type == EDIT_QF) {
      if (paramp->use_ef != NULL) {
        set_string_option_direct("ef", -1, paramp->use_ef, OPT_FREE, SID_CARG);
      }
      vim_snprintf((char *)IObuff, IOSIZE, "cfile %s", p_ef);
      if (qf_init(NULL, (char *)p_ef, p_efm, true, (char *)IObuff, (char *)p_menc) < 0) {
        msg_putchar('\n');
        os_exit(3);
      }
      TIME_MSG("reading errorfile");
    }
  }
  
  /*
   * Need to jump to the tag before executing the '-c command'.
   * Makes "vim -c '/return' -t main" work.
   */
  static void handle_tag(char_u *tagname)
  {
    if (tagname != NULL) {
      swap_exists_did_quit = false;
  
      vim_snprintf((char *)IObuff, IOSIZE, "ta %s", tagname);
      do_cmdline_cmd((char *)IObuff);
      TIME_MSG("jumping to tag");
  
      // If the user doesn't want to edit the file then we quit here.
      if (swap_exists_did_quit) {
        getout(1);
      }
    }
  }
  
  /// Read text from stdin.
  static void read_stdin(void)
  {
    // When getting the ATTENTION prompt here, use a dialog.
    swap_exists_action = SEA_DIALOG;
    no_wait_return = true;
    bool save_msg_didany = msg_didany;
    set_buflisted(true);
    // Create memfile and read from stdin.
    (void)open_buffer(true, NULL, 0);
    if (buf_is_empty(curbuf) && curbuf->b_next != NULL) {
      // stdin was empty, go to buffer 2 (e.g. "echo file1 | xargs nvim"). #8561
      do_cmdline_cmd("silent! bnext");
      // Delete the empty stdin buffer.
      do_cmdline_cmd("bwipeout 1");
    }
    no_wait_return = false;
    msg_didany = save_msg_didany;
    TIME_MSG("reading stdin");
    check_swap_exists_action();
  }
  
  /*
   * Create the requested number of windows and edit buffers in them.
   * Also does recovery if "recoverymode" set.
   */
  static void create_windows(mparm_T *parmp)
  {
    int dorewind;
    int done = 0;
  
    /*
     * Create the number of windows that was requested.
     */
    if (parmp->window_count == -1) {      // was not set
      parmp->window_count = 1;
    }
    if (parmp->window_count == 0) {
      parmp->window_count = GARGCOUNT;
    }
    if (parmp->window_count > 1) {
      // Don't change the windows if there was a command in vimrc that
      // already split some windows
      if (parmp->window_layout == 0) {
        parmp->window_layout = WIN_HOR;
      }
      if (parmp->window_layout == WIN_TABS) {
        parmp->window_count = make_tabpages(parmp->window_count);
        TIME_MSG("making tab pages");
      } else if (firstwin->w_next == NULL) {
        parmp->window_count = make_windows(parmp->window_count,
                                           parmp->window_layout == WIN_VER);
        TIME_MSG("making windows");
      } else {
        parmp->window_count = win_count();
      }
    } else {
      parmp->window_count = 1;
    }
  
    if (recoverymode) {                   // do recover
      msg_scroll = true;                  // scroll message up
      ml_recover(true);
      if (curbuf->b_ml.ml_mfp == NULL) {   // failed
        getout(1);
      }
      do_modelines(0);                    // do modelines
    } else {
      // Open a buffer for windows that don't have one yet.
      // Commands in the vimrc might have loaded a file or split the window.
      // Watch out for autocommands that delete a window.
      //
      // Don't execute Win/Buf Enter/Leave autocommands here
      ++autocmd_no_enter;
      ++autocmd_no_leave;
      dorewind = TRUE;
      while (done++ < 1000) {
        if (dorewind) {
          if (parmp->window_layout == WIN_TABS) {
            goto_tabpage(1);
          } else {
            curwin = firstwin;
          }
        } else if (parmp->window_layout == WIN_TABS) {
          if (curtab->tp_next == NULL) {
            break;
          }
          goto_tabpage(0);
        } else {
          if (curwin->w_next == NULL) {
            break;
          }
          curwin = curwin->w_next;
        }
        dorewind = FALSE;
        curbuf = curwin->w_buffer;
        if (curbuf->b_ml.ml_mfp == NULL) {
          // Set 'foldlevel' to 'foldlevelstart' if it's not negative..
          if (p_fdls >= 0) {
            curwin->w_p_fdl = p_fdls;
          }
          // When getting the ATTENTION prompt here, use a dialog.
          swap_exists_action = SEA_DIALOG;
          set_buflisted(TRUE);
  
          // create memfile, read file
          (void)open_buffer(FALSE, NULL, 0);
  
          if (swap_exists_action == SEA_QUIT) {
            if (got_int || only_one_window()) {
              // abort selected or quit and only one window
              did_emsg = FALSE;               // avoid hit-enter prompt
              getout(1);
            }
            // We can't close the window, it would disturb what
            // happens next.  Clear the file name and set the arg
            // index to -1 to delete it later.
            setfname(curbuf, NULL, NULL, false);
            curwin->w_arg_idx = -1;
            swap_exists_action = SEA_NONE;
          } else {
            handle_swap_exists(NULL);
          }
          dorewind = TRUE;                        // start again
        }
        os_breakcheck();
        if (got_int) {
          (void)vgetc();          // only break the file loading, not the rest
          break;
        }
      }
      if (parmp->window_layout == WIN_TABS) {
        goto_tabpage(1);
      } else {
        curwin = firstwin;
      }
      curbuf = curwin->w_buffer;
      --autocmd_no_enter;
      --autocmd_no_leave;
    }
  }
  
  /// If opened more than one window, start editing files in the other
  /// windows. make_windows() has already opened the windows.
  static void edit_buffers(mparm_T *parmp, char_u *cwd)
  {
    int arg_idx;                          // index in argument list
    int i;
    bool advance = true;
    win_T *win;
    char *p_shm_save = NULL;
  
    /*
     * Don't execute Win/Buf Enter/Leave autocommands here
     */
    ++autocmd_no_enter;
    ++autocmd_no_leave;
  
    // When w_arg_idx is -1 remove the window (see create_windows()).
    if (curwin->w_arg_idx == -1) {
      win_close(curwin, true, false);
      advance = false;
    }
  
    arg_idx = 1;
    for (i = 1; i < parmp->window_count; ++i) {
      if (cwd != NULL) {
        os_chdir((char *)cwd);
      }
      // When w_arg_idx is -1 remove the window (see create_windows()).
      if (curwin->w_arg_idx == -1) {
        arg_idx++;
        win_close(curwin, true, false);
        advance = false;
        continue;
      }
  
      if (advance) {
        if (parmp->window_layout == WIN_TABS) {
          if (curtab->tp_next == NULL) {          // just checking
            break;
          }
          goto_tabpage(0);
          // Temporarily reset 'shm' option to not print fileinfo when
          // loading the other buffers. This would overwrite the already
          // existing fileinfo for the first tab.
          if (i == 1) {
            char buf[100];
  
            p_shm_save = xstrdup((char *)p_shm);
            snprintf(buf, sizeof(buf), "F%s", p_shm);
            set_option_value("shm", 0L, buf, 0);
          }
        } else {
          if (curwin->w_next == NULL) {           // just checking
            break;
          }
          win_enter(curwin->w_next, false);
        }
      }
      advance = true;
  
      // Only open the file if there is no file in this window yet (that can
      // happen when vimrc contains ":sall").
      if (curbuf == firstwin->w_buffer || curbuf->b_ffname == NULL) {
        curwin->w_arg_idx = arg_idx;
        // Edit file from arg list, if there is one.  When "Quit" selected
        // at the ATTENTION prompt close the window.
        swap_exists_did_quit = false;
        (void)do_ecmd(0, arg_idx < GARGCOUNT
            ? alist_name(&GARGLIST[arg_idx]) : NULL,
                      NULL, NULL, ECMD_LASTL, ECMD_HIDE, curwin);
        if (swap_exists_did_quit) {
          // abort or quit selected
          if (got_int || only_one_window()) {
            // abort selected and only one window
            did_emsg = FALSE;             // avoid hit-enter prompt
            getout(1);
          }
          win_close(curwin, true, false);
          advance = false;
        }
        if (arg_idx == GARGCOUNT - 1) {
          arg_had_last = true;
        }
        arg_idx++;
      }
      os_breakcheck();
      if (got_int) {
        (void)vgetc();            // only break the file loading, not the rest
        break;
      }
    }
  
    if (p_shm_save != NULL) {
      set_option_value("shm", 0L, p_shm_save, 0);
      xfree(p_shm_save);
    }
  
    if (parmp->window_layout == WIN_TABS) {
      goto_tabpage(1);
    }
    --autocmd_no_enter;
  
    // make the first window the current window
    win = firstwin;
    // Avoid making a preview window the current window.
    while (win->w_p_pvw) {
      win = win->w_next;
      if (win == NULL) {
        win = firstwin;
        break;
      }
    }
    win_enter(win, false);
  
    --autocmd_no_leave;
    TIME_MSG("editing files in windows");
    if (parmp->window_count > 1 && parmp->window_layout != WIN_TABS) {
      win_equal(curwin, false, 'b');      // adjust heights
    }
  }
  
  /*
   * Execute the commands from --cmd arguments "cmds[cnt]".
   */
  static void exe_pre_commands(mparm_T *parmp)
  {
    char **cmds = parmp->pre_commands;
    int cnt = parmp->n_pre_commands;
    int i;
  
    if (cnt > 0) {
      curwin->w_cursor.lnum = 0;     // just in case..
      sourcing_name = (char_u *)_("pre-vimrc command line");
      current_sctx.sc_sid = SID_CMDARG;
      for (i = 0; i < cnt; i++) {
        do_cmdline_cmd(cmds[i]);
      }
      sourcing_name = NULL;
      current_sctx.sc_sid = 0;
      TIME_MSG("--cmd commands");
    }
  }
  
  /*
   * Execute "+", "-c" and "-S" arguments.
   */
  static void exe_commands(mparm_T *parmp)
  {
    int i;
  
    /*
     * We start commands on line 0, make "vim +/pat file" match a
     * pattern on line 1.  But don't move the cursor when an autocommand
     * with g`" was used.
     */
    msg_scroll = TRUE;
    if (parmp->tagname == NULL && curwin->w_cursor.lnum <= 1) {
      curwin->w_cursor.lnum = 0;
    }
    sourcing_name = (char_u *)"command line";
    current_sctx.sc_sid = SID_CARG;
    current_sctx.sc_seq = 0;
    for (i = 0; i < parmp->n_commands; i++) {
      do_cmdline_cmd(parmp->commands[i]);
      if (parmp->cmds_tofree[i]) {
        xfree(parmp->commands[i]);
      }
    }
    sourcing_name = NULL;
    current_sctx.sc_sid = 0;
    if (curwin->w_cursor.lnum == 0) {
      curwin->w_cursor.lnum = 1;
    }
  
    if (!exmode_active) {
      msg_scroll = FALSE;
    }
  
    // When started with "-q errorfile" jump to first error again.
    if (parmp->edit_type == EDIT_QF) {
      qf_jump(NULL, 0, 0, FALSE);
    }
    TIME_MSG("executing command arguments");
  }
  
  /// Source system-wide vimrc if built with one defined
  ///
  /// Does one of the following things, stops after whichever succeeds:
  ///
  /// 1. Source system vimrc file from $XDG_CONFIG_DIRS/nvim/sysinit.vim
  /// 2. Source system vimrc file from $VIM
  static void do_system_initialization(void)
  {
    char *const config_dirs = stdpaths_get_xdg_var(kXDGConfigDirs);
    if (config_dirs != NULL) {
      const void *iter = NULL;
      const char path_tail[] = {
        'n', 'v', 'i', 'm', PATHSEP,
        's', 'y', 's', 'i', 'n', 'i', 't', '.', 'v', 'i', 'm', NUL
      };
      do {
        const char *dir;
        size_t dir_len;
        iter = vim_env_iter(':', config_dirs, iter, &dir, &dir_len);
        if (dir == NULL || dir_len == 0) {
          break;
        }
        char *vimrc = xmalloc(dir_len + sizeof(path_tail) + 1);
        memcpy(vimrc, dir, dir_len);
        if (vimrc[dir_len - 1] != PATHSEP) {
          vimrc[dir_len] = PATHSEP;
          dir_len += 1;
        }
        memcpy(vimrc + dir_len, path_tail, sizeof(path_tail));
        if (do_source(vimrc, false, DOSO_NONE) != FAIL) {
          xfree(vimrc);
          xfree(config_dirs);
          return;
        }
        xfree(vimrc);
      } while (iter != NULL);
      xfree(config_dirs);
    }
  
  #ifdef SYS_VIMRC_FILE
    // Get system wide defaults, if the file name is defined.
    (void)do_source(SYS_VIMRC_FILE, false, DOSO_NONE);
  #endif
  }
  
  /// Source vimrc or do other user initialization
  ///
  /// Does one of the following things, stops after whichever succeeds:
  ///
  /// 1. Execution of VIMINIT environment variable.
  /// 2. Sourcing user vimrc file ($XDG_CONFIG_HOME/nvim/init.vim).
  /// 3. Sourcing other vimrc files ($XDG_CONFIG_DIRS[1]/nvim/init.vim, …).
  /// 4. Execution of EXINIT environment variable.
  ///
  /// @return True if it is needed to attempt to source exrc file according to
  ///         'exrc' option definition.
  static bool do_user_initialization(void)
    FUNC_ATTR_WARN_UNUSED_RESULT
  {
    bool do_exrc = p_exrc;
    if (execute_env("VIMINIT") == OK) {
      do_exrc = p_exrc;
      return do_exrc;
    }
  
    char_u *init_lua_path = (char_u *)stdpaths_user_conf_subpath("init.lua");
    char_u *user_vimrc = (char_u *)stdpaths_user_conf_subpath("init.vim");
  
    // init.lua
    if (os_path_exists(init_lua_path)
        && do_source((char *)init_lua_path, true, DOSO_VIMRC)) {
      if (os_path_exists(user_vimrc)) {
        semsg(_("E5422: Conflicting configs: \"%s\" \"%s\""), init_lua_path,
              user_vimrc);
      }
  
      xfree(user_vimrc);
      xfree(init_lua_path);
      return false;
    }
    xfree(init_lua_path);
  
    // init.vim
    if (do_source((char *)user_vimrc, true, DOSO_VIMRC) != FAIL) {
      do_exrc = p_exrc;
      if (do_exrc) {
        do_exrc = (path_full_compare((char_u *)VIMRC_FILE, user_vimrc,
                                     false, true)
                   != kEqualFiles);
      }
      xfree(user_vimrc);
      return do_exrc;
    }
    xfree(user_vimrc);
  
    char *const config_dirs = stdpaths_get_xdg_var(kXDGConfigDirs);
    if (config_dirs != NULL) {
      const void *iter = NULL;
      do {
        const char *dir;
        size_t dir_len;
        iter = vim_env_iter(':', config_dirs, iter, &dir, &dir_len);
        if (dir == NULL || dir_len == 0) {
          break;
        }
        const char path_tail[] = { 'n', 'v', 'i', 'm', PATHSEP,
                                   'i', 'n', 'i', 't', '.', 'v', 'i', 'm', NUL };
        char *vimrc = xmalloc(dir_len + sizeof(path_tail) + 1);
        memmove(vimrc, dir, dir_len);
        vimrc[dir_len] = PATHSEP;
        memmove(vimrc + dir_len + 1, path_tail, sizeof(path_tail));
        if (do_source(vimrc, true, DOSO_VIMRC) != FAIL) {
          do_exrc = p_exrc;
          if (do_exrc) {
            do_exrc = (path_full_compare((char_u *)VIMRC_FILE, (char_u *)vimrc,
                                         false, true) != kEqualFiles);
          }
          xfree(vimrc);
          xfree(config_dirs);
          return do_exrc;
        }
        xfree(vimrc);
      } while (iter != NULL);
      xfree(config_dirs);
    }
  
    if (execute_env("EXINIT") == OK) {
      do_exrc = p_exrc;
      return do_exrc;
    }
    return do_exrc;
  }
  
  /// Source startup scripts
  static void source_startup_scripts(const mparm_T *const parmp)
    FUNC_ATTR_NONNULL_ALL
  {
    // If -u given, use only the initializations from that file and nothing else.
    if (parmp->use_vimrc != NULL) {
      if (strequal(parmp->use_vimrc, "NONE")
          || strequal(parmp->use_vimrc, "NORC")) {
        // Do nothing.
      } else {
        if (do_source(parmp->use_vimrc, false, DOSO_NONE) != OK) {
          semsg(_("E282: Cannot read from \"%s\""), parmp->use_vimrc);
        }
      }
    } else if (!silent_mode) {
      do_system_initialization();
  
      if (do_user_initialization()) {
        // Read initialization commands from ".vimrc" or ".exrc" in current
        // directory.  This is only done if the 'exrc' option is set.
        // Because of security reasons we disallow shell and write commands
        // now, except for unix if the file is owned by the user or 'secure'
        // option has been reset in environment of global "exrc" or "vimrc".
        // Only do this if VIMRC_FILE is not the same as vimrc file sourced in
        // do_user_initialization.
  #if defined(UNIX)
        // If vimrc file is not owned by user, set 'secure' mode.
        if (!file_owned(VIMRC_FILE))
  #endif
        secure = p_secure;
  
        if (do_source(VIMRC_FILE, true, DOSO_VIMRC) == FAIL) {
  #if defined(UNIX)
          // if ".exrc" is not owned by user set 'secure' mode
          if (!file_owned(EXRC_FILE)) {
            secure = p_secure;
          } else {
            secure = 0;
          }
  #endif
          (void)do_source(EXRC_FILE, false, DOSO_NONE);
        }
      }
      if (secure == 2) {
        need_wait_return = true;
      }
      secure = 0;
    }
    TIME_MSG("sourcing vimrc file(s)");
  }
  
  /// Get an environment variable, and execute it as Ex commands.
  ///
  /// @param env         environment variable to execute
  ///
  /// @return FAIL if the environment variable was not executed,
  ///         OK otherwise.
  static int execute_env(char *env)
    FUNC_ATTR_NONNULL_ALL
  {
    const char *initstr = os_getenv(env);
    if (initstr != NULL) {
      char_u *save_sourcing_name = sourcing_name;
      linenr_T save_sourcing_lnum = sourcing_lnum;
      sourcing_name = (char_u *)env;
      sourcing_lnum = 0;
      const sctx_T save_current_sctx = current_sctx;
      current_sctx.sc_sid = SID_ENV;
      current_sctx.sc_seq = 0;
      current_sctx.sc_lnum = 0;
      do_cmdline_cmd((char *)initstr);
      sourcing_name = save_sourcing_name;
      sourcing_lnum = save_sourcing_lnum;
      current_sctx = save_current_sctx;
      return OK;
    }
    return FAIL;
  }
  
  #ifdef UNIX
  /// Checks if user owns file.
  /// Use both uv_fs_stat() and uv_fs_lstat() through os_fileinfo() and
  /// os_fileinfo_link() respectively for extra security.
  static bool file_owned(const char *fname)
  {
    assert(fname != NULL);
    uid_t uid = getuid();
    FileInfo file_info;
    bool file_owned = os_fileinfo(fname, &file_info)
                      && file_info.stat.st_uid == uid;
    bool link_owned = os_fileinfo_link(fname, &file_info)
                      && file_info.stat.st_uid == uid;
    return file_owned && link_owned;
  }
  #endif
  
  /// Prints the following then exits:
  /// - An error message `errstr`
  /// - A string `str` if not null
  ///
  /// @param errstr  string containing an error message
  /// @param str     string to append to the primary error message, or NULL
  static void mainerr(const char *errstr, const char *str)
    FUNC_ATTR_NORETURN
  {
    char *prgname = (char *)path_tail((char_u *)argv0);
  
    signal_stop();              // kill us with CTRL-C here, if you like
  
    mch_errmsg(prgname);
    mch_errmsg(": ");
    mch_errmsg(_(errstr));
    if (str != NULL) {
      mch_errmsg(": \"");
      mch_errmsg(str);
      mch_errmsg("\"");
    }
    mch_errmsg(_("\nMore info with \""));
    mch_errmsg(prgname);
    mch_errmsg(" -h\"\n");
  
    os_exit(1);
  }
  
  /// Prints version information for "nvim -v" or "nvim --version".
  static void version(void)
  {
    // TODO(bfred): not like this?
    nlua_init();
    info_message = true;  // use mch_msg(), not mch_errmsg()
    list_version();
    msg_putchar('\n');
    msg_didout = false;
  }
  
  /// Prints help message for "nvim -h" or "nvim --help".
  static void usage(void)
  {
    signal_stop();              // kill us with CTRL-C here, if you like
  
    mch_msg(_("Usage:\n"));
    mch_msg(_("  nvim [options] [file ...]      Edit file(s)\n"));
    mch_msg(_("  nvim [options] -t <tag>        Edit file where tag is defined\n"));
    mch_msg(_("  nvim [options] -q [errorfile]  Edit file with first error\n"));
    mch_msg(_("\nOptions:\n"));
    mch_msg(_("  --                    Only file names after this\n"));
    mch_msg(_("  +                     Start at end of file\n"));
    mch_msg(_("  --cmd <cmd>           Execute <cmd> before any config\n"));
    mch_msg(_("  +<cmd>, -c <cmd>      Execute <cmd> after config and first file\n"));
    mch_msg("\n");
    mch_msg(_("  -b                    Binary mode\n"));
    mch_msg(_("  -d                    Diff mode\n"));
    mch_msg(_("  -e, -E                Ex mode\n"));
    mch_msg(_("  -es, -Es              Silent (batch) mode\n"));
    mch_msg(_("  -h, --help            Print this help message\n"));
    mch_msg(_("  -i <shada>            Use this shada file\n"));
    mch_msg(_("  -m                    Modifications (writing files) not allowed\n"));
    mch_msg(_("  -M                    Modifications in text not allowed\n"));
    mch_msg(_("  -n                    No swap file, use memory only\n"));
    mch_msg(_("  -o[N]                 Open N windows (default: one per file)\n"));
    mch_msg(_("  -O[N]                 Open N vertical windows (default: one per file)\n"));
    mch_msg(_("  -p[N]                 Open N tab pages (default: one per file)\n"));
    mch_msg(_("  -r, -L                List swap files\n"));
    mch_msg(_("  -r <file>             Recover edit state for this file\n"));
    mch_msg(_("  -R                    Read-only mode\n"));
    mch_msg(_("  -S <session>          Source <session> after loading the first file\n"));
    mch_msg(_("  -s <scriptin>         Read Normal mode commands from <scriptin>\n"));
    mch_msg(_("  -u <config>           Use this config file\n"));
    mch_msg(_("  -v, --version         Print version information\n"));
    mch_msg(_("  -V[N][file]           Verbose [level][file]\n"));
    mch_msg("\n");
    mch_msg(_("  --api-info            Write msgpack-encoded API metadata to stdout\n"));
    mch_msg(_("  --embed               Use stdin/stdout as a msgpack-rpc channel\n"));
    mch_msg(_("  --headless            Don't start a user interface\n"));
    mch_msg(_("  --listen <address>    Serve RPC API from this address\n"));
    mch_msg(_("  --noplugin            Don't load plugins\n"));
    mch_msg(_("  --remote[-subcommand] Execute commands remotely on a server\n"));
    mch_msg(_("  --server <address>    Specify RPC server to send commands to\n"));
    mch_msg(_("  --startuptime <file>  Write startup timing messages to <file>\n"));
    mch_msg(_("\nSee \":help startup-options\" for all options.\n"));
  }
  
  
  /*
   * Check the result of the ATTENTION dialog:
   * When "Quit" selected, exit Vim.
   * When "Recover" selected, recover the file.
   */
  static void check_swap_exists_action(void)
  {
    if (swap_exists_action == SEA_QUIT) {
      getout(1);
    }
    handle_swap_exists(NULL);
  }
  